Where I think aikido should borrow and happily steal from any and all other arts is in the attacks, which, as has been alluded to before, I feel is the area of cross training that would benefit aikido the most.

Nice question, now bugger off and train.

Firstly thanks to Larry for opening this.

I'd have to agree with Ian as above. I've been at seminars where the attacks from fellow Aikidoka are pathetic. Shomenuchis that veer off from the head following the invisible forcefield around my body (hey if I don't move, hit me!) and Yokomens that remind me of being slapped with a wet lettuce (least said, soonest mended), and these from black belt toting hakama wearing exponents of the art.

At that level in a martial art you should be able to at least hit someone!

Technique number one in Wing Chun, the straight punch. Most people can do a halfway decent version by the end of the first lesson.

Half drunk people in bars usually manage a committed version of shomenuchi with a beer bottle in their hands!

*rant off*

The other side of the equation is the cry of, "You attacked me wrong." as people come stuttering to the end of what they were expecting to do.

Perhaps a culture of deal with the attack, whatever it is, and then say something like, "Now could you do the attack that we're training please." might go some way to sorting this.

I'm very lucky, I train in a dojo where we don't seem to have these problems but when you come across them in other places it can lead to asking a variant of Larry's question and it doesn't do anything for the rep of Aikido as a martial art.